Flybe have opted for T3, which, don't forget, will be connected to T2 by both airside and landslide links, so, transfers should not be an issue (even if there is a slight walk).
Let's not forget, BE codeshare/interlink with EK and TCX in T1 and CX in T2, so, the fact they stay in T3 while their connection partners are in T2 shouldn't,t be an issue.
Also, th Dash 8 doesn't use air bridges, and apparently MAG want the vast majority, if not all, the T2 carriers to use contact stands. One of the main purposes of this projects is to increase contact stands (as well as improve the pax experience).
United would be 3 daily next summer, the same as EDI.